[150cchamp]

i have a 2006 crf150f and just recently it started bogging and backfiring really bad and lost acceleration completely when i twist the throttle it dies out or wants to die out.what anyone have any idea of why this is happening? I re jetted my bike 2 days before this started but i don't think its that because it was running like a champ for 2 days

[crfsonly]

did you do anything with the fuel screw? check to make sure you have lost it. check to make sure the one or more of the jets may have fallen out. check air boots and make sure the clamps are secure and boot is fitted correctly.

[150cchamp]

fuel screw as in idle screw? not really idle is fine but there is this thing on bottom of carb it looks like a screw should be there but its just a flat circle and no flat head or philips hole to screw in and out with

[crfsonly]

http://partsfinder.onlinemicrofiche.com ... 3&A=89&B=7

item #6 is the fuel screw in the diagram in the link above.

[150cchamp]

yup and its like a half moon shape i have to get a special tool to adjust it. do you think this is the problem

[crfsonly]

i don't know what is causing it as i'm not there to inspect and eliminate what isn't the problem. it could be several things. you should do as i mentioned in my first post:

1. check the jets you installed and make sure they are still installed

2. check your fuel screw and make sure it has not fallen out (doesn't sound like it has). if you didn't adjust it (sounds like you didn't) then just let it be.

3. check the air boot between the carb and the engine and make sure it's installed correctly.

4. make sure the header/exhaust is installed correctly and tightened down.

5. make sure your air filter is installed correctly and not torn.

ken

[150cchamp]

everything is fine jets are in air filter is fine everything you suggested looks good to me....

[crfsonly]

did you actually check the jets? check the needle? check the exhaust header to head connection? the symptoms you are describing sounds like a lean situation (too much air not enough fuel). if you were in the carb before this happened then you have verify the work you did was correct and didn't introduce this problem. if all is correct then i'd recommend you go back to the jetting you had prior to your installing new jets and see the results. also make sure your vent tube in the gas cap is venting. check electrical connections. good luck!